<!DOCTYPE html>
<html lang="en">
<head>
		<meta charset="utf-8">
		<title></title>
		<script type="text/javascript">
			const cnNum=new Array('零', '壹', '贰', '叁', '肆', '伍', '陆', '柒', '捌', '玖')
			const unit=new Array('萬','仟','佰', '拾','亿','仟','佰', '拾', '萬','仟','佰', '拾','元','角','分')
			function fun(){
				let num=document.getElementById("num").value
				num = num.trim()  //处理不可视的空格
				let reg=/^\d{1,13}(\.\d{1,})?$/
				 if (!reg.test(num)) {
					alert("数字格式错误")
				    return;
				}	
				let intPart;
				let decPart;
				var index =num.indexOf(".")
				if(index<0){
					intPart=num-0+"" //消除有效数前面0；加"",将其变成字符串
					decPart="00"
				}else{
					intPart=num.substring(0,index)-0+"" //substring(i,j)--[i,j)
					decPart=(num+"0").substr(index+1,2)
				}
				//银行金额
				let res1=""
				for (var i = intPart.length; i >0; i=i-3) {
					if(i-3<=0){
						res1=intPart.substring(0,i)+res1
					}else{
						res1 ="," +intPart.substring(i-3,i)+res1
					}
				}
				document.querySelector("#num1").textContent=res1+"."+decPart
				//大写转换
				let res2=""
				let money=intPart+decPart
				for (var i = money.length-1,j=unit.length-1; i >=0; i--,j--){
					res2=cnNum[money[i]]+unit[j]+res2
				}
				document.querySelector("#num2").textContent=res2
			}
		</script>
</head>
<body>
    输入数字：<input type="text" id="num" ><button onclick="fun()">转换</button><br>
    银行金额：<span id="num1"></span><br>
    大写金额：<span id="num2"></span><br>

  